Re: A very brief standards reivew…
Actually, I think it’ll be more useful when <!DOCYPE HTML> is used and widely supported by user agents, but that’s a whole other story. (http://www.whatwg.org/specs/web-apps/current-work/#the-doctype)
My point was more about serving up the correct content type, based on the DOCTYPE used. Serving XHTML 1.1 as text/html merits no benefits. It’s tag soup.
I would think that at least using some sort of content negotiation based on the user agent (serving HTML 4.01 Strict versus XHTML 1.1) would be a good start.